1. Field of the Invention
This invention relates to improvements of strobe re-actuating devices, and more particularly to methods for advantageously controlling actuation of strobe charging.
2. Description of the Prior Art
Recently, a camera having an automatic actuation type strobe in which, as it darkens, shooting is automatically accompanied by a firing of the strobe has been proposed, and it is becoming possible to always obtain properly exposed shootings without the necessity of elaborate management. In this automatic firing type probe, to insure that firing can take place at any time the main condenser for storing a charge which is convertible to flashed light must always be fully charged after the preceding exposure has been completed. For this purpose, a method is known for actuating the DC/DC converter each time the release button moves backward from ON to OFF at the first stroke, or the film is advanced one frame (U.S. Pat. No. 4,441,774). By this method, the strobe is always ready for the next exposure with flash illumination. As a result, in a continuous series of flash exposures, improvement of the frame speed is achieved.
Since the use of this method, however, provides recyclic actuation of the strobe for each shot without exception, it follows that even if the strobe was not fired with the preceding exposure since the object is very bright, the DC/DC converter is recyclically actuated, thereby being at a disadvantage in that premature consumption of the battery results. Therefore, the total number of flash exposures per one battery charge is reduced. Another disadvantage arising from premature consumption of the parts concerning the charging of the strobe is that the number of faulty operations is increased. Furthermore, because the re-actuating operation has to be carried out regardless of what charging condition the strobe is in, even if the strobe remains in the fully charged condition, or the brightness level is so high as not to necessitate flash illumination, the photographer must wait a certain time before the next daylight exposure. Thus, there has been a problem of increasing the time interval between two successive daylight exposures.
A first object of the invention is to eliminate the above-described conventional problems and to provide a strobe re-actuating device for a camera capable of preventing wasteful strobe charging actuation from being recycled when the strobe is in the fully charged state, or the brightness level of an object to be photographed does not necessitate the strobe, thereby the life time of the battery is increased, and the shooting speed is improved.
This and other objects and features of the invention will become apparent from the following descriptions of the embodiments thereof.